Mark Zuckerberg's sister angered after family Facebook photo goes public

The confusion around Facebook's oft-criticized privacy settings hit close to home for founder Mark Zuckerberg, when his sister noticed that a photo she had meant to be private went public.

On Christmas Day, Randi Zuckerberg posted a Facebook photo of her family -- including Mark -- reacting in mock surprise to the company's new Poke app. When Callie Schweitzer, Vox Media's director of marketing, saw the photo at the top of her feed, she assumed it was public and promptly tweeted it to her followers.

Surprised and unhappy, Zuckerberg lashed out at Schweitzer in a since-deleted tweet: "@cschweitz: Not sure where you got this photo. I posted it only to friends on FB. You reposting it on Twitter is way uncool."

Schweitzer immediately apologized and deleted the offending tweet, explaining that she thought the photo was meant for everyone to see.

@cschweitz would really appreciate if you would delete the original tweet where you posted the photo. No need to spread it further. Thanks!

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